I am preparing a feature film production where we will use the Alexa SXT and anamorphic lenses.

To be cost-efficient, we were thinking about using the 6:5 Mode (ProRes 2K Anamorphic) which does not take too much storage space and which sounds like a nice solution.

But as we also have some VFX shots in the movie, the question arises whether it might be good to use another mode for the VFX shots.

Would 4:3 ProRes 2.8K be a better solution? I kind of doubt it, that it helps a lot. If I understand it correctly, we would have some more "flesh" on the left and right, but would be using the same height?

Or should ARRIRAW considered for the VFX shots? If yes, which mode should be used with ARRIRAW?